<<

. 14
( 62 .)



>>

debate
Individualism about the mind was introduced as a form of methodological
solipsism in considering the nature of an individual™s mental life and how
we ought to theorize systematically about it. I drew on this conception
of individualism in discussing the disciplining of psychology as a ¬eld
of inquiry and nativism about the mind. In Chapter 1, I also provided a
more precise characterization of individualism in psychology in terms of
the notion of supervenience.
It is sometimes unclear to those outside of the philosophy of mind just
how either the methodological solipsism or the supervenience formu-
lation of individualism could give rise to a substantive debate about the
mind and its study. Consider construals of each of these formulations that
make either individualism or externalism seem trivially true.
Methodological solipsism in psychology is the view that psychologi-
cal states should be construed without reference to anything beyond the
boundary of the individual who has those states. It is in light of this view
that the debate between individualists and externalists has sometimes
been glossed in terms of whether psychological or mental states are
“in the head.” But to the initiated and uninitiated alike, that is likely
to sound like a puzzling issue to debate: Of course mental states are in
the head! (“Where else could they be?,” as Robert Stalnaker once asked.)
So this construal of individualism makes externalism a nonstarter, and so
individualism seem trivially true.


77
Individualism and Externalism in Cognitive Sciences
78

The supervenience formulation of individualism says that mental states
supervene on the intrinsic, physical properties of the individual who bears
them. The most important feature of the central relation of superve-
nience, at least for our purposes, is that it is determinative: According to
the individualist, an individual™s mental states are determined by her in-
trinsic, physical states. But then it seems that it is individualism that is
a nonstarter, for surely, one might think, there are many environmental
factors that determine what mental states an individual ends up having.
What visual perceptions you have are determined by what™s in front of
you, and what sorts of things you think about is determined, in part, by
what concepts you have been taught “ by parents, siblings, peers, and
teachers. So construed, externalism seems trivially true.
Both of these construals of the issue that separates individualists from
externalists about the mind are, of course, caricatures. But I hope they will
be useful caricatures, in several ways. First, the ease with which they can be
derived from each characterization of individualism poses a challenge: to
articulate a version of the issue separating individualists and externalists
that makes more perspicuous why individualism is a substantive and thus
potentially controversial claim about the nature of the mind and how we
should study it. Second, I think that each caricatured objection contains
more than a grain of truth about, respectively, externalism and individ-
ualism. And so part of our task in responding to the above challenge in
the next section will be to sift the true from the false in each of these
caricatures.
In section 3, I review the original arguments for externalism provided
by Hilary Putnam and Tyler Burge. Both of these arguments appeal to
claims about intentionality or content, but the issues they raise concern
psychological states in general. Burge concluded his original critique by
saying that the “sense in which man is a social animal runs deeper than
much mainstream philosophy of mind has acknowledged.” In section 4,
I show just how externalism suggests that the social aspects to having a
mind run deeper than a range of in¬‚uential philosophical views have
allowed.1
If individualism is as entrenched a view in the history of philosophy and
in contemporary analytic philosophy as sections 2“4 imply, then it should
be no surprise that the conclusions from the Putnam-Burge arguments
have been resisted. The remainder of the chapter aims to give the ¬‚avor of
this resistance. In section 5, I discuss perhaps the most prevalent response,
one that draws on a distinction between narrow and wide content. The
idea that there is some notion of content immune to the Putnam-Burge
Individualism: Philosophical Foundations 79

arguments is popular even if problematic. Section 6 explores the prima
facie relationship between individualism, functionalism, and physicalism,
and section 7 reviews and critiques an in¬‚uential argument for individu-
alism that purports to show that individualism in psychology is mandated
by re¬‚ection on the nature of scienti¬c taxonomy more generally.
The chapter as a whole aims to be a self-contained philosophical
primer on individualism about the mind. At its end, we will be in a better
position to lay the foundations for an alternative, externalist conception
of the mind.


2 individualism, taxonomy, and metaphysical
determination
Externalists don™t claim that mental states are somewhere other than in
the head, and individualists don™t think that what is outside the head has
nothing to do with what ends up in the head. The key to understanding
the debate between individualists and externalists about the mind lies in
grasping the notion of determination at its heart.
Individualists and externalists agree that an individual™s environment is
a causal determinant of that individual™s thoughts and thus mind. Agents
causally interact with their world, gathering information about it through
their senses, and through their communicative interactions with others.
Thus, the nature of their minds, in particular what their thoughts are
about, is in part causally determined by the character of their world.
That is, the world is a contributing or ef¬cient cause to the content of
one™s mind, to what one perceives, desires, and thinks about. This is just
to say that the content of one™s mind is not causally isolated from one™s
environment. Separating individualists and externalists is the question of
whether there is some deeper sense in which the nature of the mind is
determined by the character of the individual™s world. It is this “deeper
sense” of world-mind determination that we need to articulate further.
We can approach this issue by extending the brief discussion of the
idea that the content of the mind is in part causally determined by the
agent™s environment to explore the conditions under which a difference
in the world implies a difference in the mind. Individualists hold that this
is so just in case that difference in the world makes some corresponding
change to what occurs inside the boundary of the individual. Externalists
deny this, thus allowing for the possibility that individuals who are iden-
tical with respect to all of their intrinsic features could nonetheless have
psychological or mental states with different contents. And, assuming
Individualism and Externalism in Cognitive Sciences
80

that mental states with different contents are ipso facto different types
or kinds of states, this implies that an individual™s intrinsic properties do
not determine or ¬x that individual™s mental states.
Thus, to state individualism adequately, we need to draw a distinction
between causal and metaphysical determination. Individualists claim, and
externalists deny, that what occurs inside the boundary of an individual
metaphysically determines the nature of that individual™s mental states.
The individualistic determination thesis, unlike the causal determination
thesis, expresses a view about the nature or essence of mental states, and
identi¬es a way in which, despite their causal determination by states of
the world, mental states are, according to individualists, autonomous or
independent of the character of the world beyond the individual.
I said in the previous section that the relation of supervenience was
determinative, and we can now see that the appropriate notion of de-
termination is that of metaphysical, rather than causal, determination.
The determining properties “ for individualists, the intrinsic, physical
properties of the individual “ are called the subvenient or base properties.
Once subvenient or base properties are ¬xed or held constant across
two or more situations, the supervening properties “ in this case, the
individual™s mental properties “ are also ¬xed across those situations.
Many of an individual™s properties, particularly those that are of inter-
est to scientists, supervene on that individual™s intrinsic, physical prop-
erties. To take a simplistic example, it is plausible to suppose that your
mass supervenes on the mass of all of the particles in your body. Given
this supposition, it doesn™t matter what else is true or false about you: If
the mass of all the particles in your body is 100 kg, then your mass is also
100 kg. Provided that the mass of all the particles in your body is 100 kg,
it doesn™t matter whether you are on Earth or on Mars, whether you are
stationary or in motion, or whether you are rapidly losing or gaining
particles, your mass is also 100 kg. There is no way to change your mass
from 100 kg that does not also change the mass of all of the particles in
your body. We might say that mass is compositionally or mereologically
determinative: The masses of any physical thing™s components or parts
metaphysically determine its mass.
If you are injected with a liquid that increases your mass by 1 kg, that
action also increases the mass of the particles in your body by a total of
1kg “ say, either because of the mass of the particles in the liquid itself, or
because of the way in those particles interact chemically with the particles
already in your body, thus adjusting their number and mass. Alternatively,
if someone removes a part of your body “ an arm, a kidney, a piece of
Individualism: Philosophical Foundations 81

skin “ and your mass is subsequently reduced, the mass of all of the par-
ticles in your body is reduced by precisely the same amount. At least this
is true provided that a person™s mass supervenes on just the mass of all
of the particles in her body, that is, that mass is mereologically determi-
native. (Note that the theory of special relativity provides no grounds for
denying this view, since although an object™s mass varies with its velocity,
so too does the mass of its physical parts.)
The idea that mental properties should be assimilated to properties
explored in the physical sciences, such as mass, has provided one power-
ful reason for thinking that psychology must or should be individualistic.
If the distinction between causal and metaphysical determination shows
what is mistaken about the caricature of individualism that makes exter-
nalism appear trivially true, then this assimilation between the mental
and the physical helps to explain the grain of truth in the caricaturized
picture of individualism with which we began. For what is right about
the caricature is that individualists do place an emphasis on the central
role that an individual™s intrinsic, physical properties play in the causal
economy of that individual. This has sometimes been summarized in the
slogan “No mental difference without an intrinsic physical difference.”
That many see such a slogan as derivative from the physicalist slogan
“No difference without a physical difference” points to one perceived
link between individualism and physicalism. (More of which in sections 6
and 7.)
Let us return to the methodological solipsism formulation of individ-
ualism to see both why externalists are not committed to denying that
mental states are “in the head,” and why this caricature nonetheless cap-
tures something true about externalism. Even though individualism is a
thesis of metaphysical determination, it is also a claim about how psycho-
logical states ought to be individuated or taxonomized. This is implicit,
I think, in the adjectives “mental,” “psychological,” or “cognitive,” pred-
icated of states, properties, processes, or events, since to talk of (say)
mental properties is already to talk of properties as being of a certain
kind or type. Thus, although individualists and externalists agree that
mental states are “in the head” “ just as they agree that they are causally
determined, in part, by what lies beyond the head “ they disagree about
how mental states should be individuated or taxonomized. What is right
about the caricature of externalism, then, is that externalists do think that
what lies beyond the head, what is not “in the head,” is relevant to psy-
chological taxonomy. What psychological kinds an individual instantiates
is not metaphysically determined by what is in the head.
Individualism and Externalism in Cognitive Sciences
82

We can now put together the point about determination with this claim
about taxonomy. Individualism is the view that mental states, qua mental
states, are metaphysically determined by an individual™s intrinsic, physical
properties. The expression “mental states” is used in a general sense,
and encompasses determinate forms of states, properties, processes, and
events that are termed “mental,” including kinds that are motivational,
cognitive, and perceptual.
Individualists are right to think that the cognitive and physical sciences
are subject to similar constraints, but wrong, I shall suggest, about what
those constraints are. Talk of mental states being “in the head” may be a
useful shorthand for the individualistic claim that such states, insofar as
they feature in psychological taxonomies, are metaphysically determined
by an individual™s intrinsic, physical properties. But we should also be wary
of how readily this locational metaphor can mislead us about the nature
of the debate between individualists and externalists.
As a thesis of metaphysical determination, individualism implies that
two individuals identical in their intrinsic respects must have the same
psychological states. The modal aspect to this implication makes super-
venience an appropriate concept to use in stating individualism more
precisely. This implication, and indeed the debate over individualism, is
often made more vivid through the fantasy of doppelg¨ ngers, molecule-for-
a
molecule identical individuals, and the corresponding fantasy of Twin
Earth. I turn to these dual fantasies next.


3 getting to twin earth: what™s in the head?
Hilary Putnam™s “The Meaning of ˜Meaning™” introduced both fantasies
in the context of a discussion of the meaning of natural language terms.
Putnam was concerned to show that “meaning” does not and cannot
jointly satisfy two theses that it was often taken to satisfy by then prevalent
views of natural language reference: the claim that the meaning of a term
is what determines its reference, and the claim that knowing the meaning
of a term is simply a matter of being in a particular psychological state.
This latter claim is sometimes glossed by saying that meanings are “in the
head,” and it is an individualistic claim in that it implies that knowledge
of meaning is metaphysically determined by what™s inside the head.
These theses typi¬ed descriptive theories of reference, prominent
since Gottlob Frege and Bertrand Russell explicitly formulated them,
according to which the reference of a term is ¬xed or metaphysically
determined by the descriptions that a speaker attaches to that term.
Individualism: Philosophical Foundations 83

Such views were central to both ordinary language philosophy and logi-
cal empiricism, two encompassing frameworks that had much in¬‚uence
in English-speaking philosophy throughout the 1950s and 1960s. The
basic idea of descriptive theories of reference is perhaps best conveyed
through an example.2
Suppose that I think of Aristotle as a great, dead philosopher who wrote
a number of important philosophical works, such as the Nicomachean
Ethics, and who was a student of Plato and teacher of Alexander the Great.
These are the descriptions that I associate with the name “Aristotle.”
Then, on a descriptivist view of reference, the reference of my term
“Aristotle” is just the thing in the world that satis¬es the various descrip-
tions that I attach to that term: It is the thing in the world that is a great
philosopher, is dead, wrote a number of important philosophical works,
was a student of Plato, and was a teacher of Alexander the Great. Such
descriptivist views of the reference of proper names were the critical fo-
cus of Saul Kripke™s in¬‚uential Naming and Necessity, while in his attack
on this cluster of views and their presuppositions, Putnam focused on
natural kind terms, such as “water” and “tiger.” Both Kripke and Putnam
intended their critiques and the subsequent alternative theory of natural
language reference, the causal theory of reference, to provide another,
general way to think about the relationship between language and the
world. As Gary Ebbs has pointed out, in at least Putnam™s case, this the-
ory was part and parcel of a more wide-ranging critique of the notions
of analyticity, the a priori, and reductionism associated with empiricist
views in metaphysics and the philosophy of science. But let us stay close
to Putnam™s argument in “The Meaning of ˜Meaning™” and draw out its
connection to individualism.3
Consider an ordinary individual, Oscar, who lives on Earth and in-

<<

. 14
( 62 .)



>>